added a note about sharing of nbconvert tempates

IPython/nbconvert/templates/README.md

@@ -0,0 +1,9 b''
+README FIRST
+============
+
+Please do not add new templates for nbconvert here.
+
+In order to speed up the distribution of nbconvert templates and make it
+simpler to share such contributions, we encourage [sharing those links on our
+wiki
+page](https://github.com/ipython/ipython/wiki/Cookbook:%20nbconvert%20templates).

IPython/nbconvert/templates/skeleton/README.md

@@ -1,8 +1,12 b''
 ## Template skeleton
 
 This directory contains the template skeleton files.
 
 Do not modify the contents of the `../latex/skeleton` folder.  Instead, 
 if you need to, make modifications to the files in this folder and then run
 `make` to generate the corresponding latex skeleton files in the 
-`../latex/skeleton` folder.
  No newline at end of file
+`../latex/skeleton` folder.
+
+If you would like to share your resulting templates with others, we encourage
+[sharing those links on our wiki
+page](https://github.com/ipython/ipython/wiki/Cookbook:%20nbconvert%20templates).